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Currently I power my table saw and jointer on a 240 volt breaker with 12 gauge wire. Both are 3HP motors.
Can I run a single phase 5HP 240 volt grizzly jointer on the same line?
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10-17-2018, 05:21 PM
(This post was last modified: 10-17-2018, 05:22 PM by Phil Thien.)
I think you're going to need at least 10-AWG wire and a 30A breaker for that thing.
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If you go to the Grizzly web site, the jointer you are considering will have a SPECIFICATION SHEET you can click on. It will list the recommended circuit breaker size.
I think you'll find that Phil is correct - a 30 amp circuit is usually recommended for a 5hp tool.
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Grizzly's current offerings only include two jointers with 5 hp single-phase motors. One shows 19A, and the other is 25A.
30A is fine for the lower current unit, even though the NEC requires 28A design current at 230V single-phase for a 5 hp motor (for wiring and disconnects, not for overload protection). 30A is probably fine for the 25A motor*, but technically it should be on a 35A circuit if it is.
Barring unforeseen information to the contrary, I'd just run a 30A circuit on 10-gauge copper and go to work.
*Asian motors tend to the high end of the NEC motor current range, as a general rule.
Tom
“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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I currently have a double pole 240 volt breaker coded 20 amps. Grizzly’s specs call for 30 amps and 12 gauge wire. Could I merely just replace the breaker? Also, do I need a double pole 30 amp breaker and if I put in a separate line do I need 10 gauge wire?
Thanks.
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(10-18-2018, 04:22 AM)Gibbcutter Wrote: I currently have a double pole 240 volt breaker coded 20 amps. Grizzly’s specs call for 30 amps and 12 gauge wire. Could I merely just replace the breaker? Also, do I need a double pole 30 amp breaker and if I put in a separate line do I need 10 gauge wire?
Thanks.
No, to your first question. You need to replace the wire too. You'll generate heat trying to pull 25 amps through a 12ga wire. The breaker determines the wire size.
Second question. Yes, 230 volts requires a two pole breaker. Yes you need 10 ga wire.
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I’m be using a 2 pole 30 amp breaker running 10 gauge wire. Any problems if the distance between the electrical panel and the outlet is 65’?
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10-24-2018, 02:35 PM
(This post was last modified: 10-24-2018, 02:42 PM by TDKPE.)
Let's see - 1.25 ohms/1000 ft (approx) and a round-trip distance of 2 x 65 ft is 0.16 ohms.
24A (80% of 30A for motor loads) Using the full circuit rating since I don't remember what your actual motor rated current is, 30A x 0.16 ohms is 4.8 volts dropped over that distance, not counting machine cord and feeder or service cabling to the panel. 4.8V/240V x 100% is 2% voltage drop. Or, 240V - 4.8V = 235V. Well within the -10% allowable (216V) at the utilization equipment (-5% for the utility, and another -5% for the feeder and branch circuits), assuming you actually have 240V to start with. But even if the utility is sagging to the -5% limit of 228V, you're still less than -5% for the feeder (if present) and branch circuit at 223V.
I'd say you're good to go.
Tom
“This place smells like that odd combination of flop sweat, hopelessness, aaaand feet"
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10-24-2018, 02:55 PM
(This post was last modified: 10-24-2018, 03:13 PM by Gibbcutter.)
Little trouble with the detailed analysis but I understood the punchline.
Thanks.